RSS Help

I’m pretty new at this…. I’ve spent some time this morning looking through several posts on this subject, and keep coming back to the same base issue. My blog is http://www.carswellgroup.net . I have a custom theme that came with an RSS button, which does not work. I’ve tried the standby of http://www.carswellgroup.net/feed – and I get a 404 error. My hope is to eventually sign people up for a daily email of my blog, but for now I think the feed will be good to get me started… can someone please help?